Every normal subject excretes methylated purines, pyrimidines and some of their breakdown products in urine. It was found that these products originate from the turnover of tRNA. tRNA modification and metabolism are aberrant in tumor tissue, and the rate of turnover of tRNA in tumor tissue is highly elevated. Consequently, cancer patients excrete elevated levels of modified nucleosides and products derived from them. Sensitive, accurate analytical procedure for the determination of nucleosides in one milliliter of spot sample of urine relative to the creatinine content has been perfected. Some of these markers are significantly elevated in the urine of every cancer patient examined. It has been determine that in two populations at risk of cancer, urinary nucleoside markers are elevated before the evidence of patent malignancy. These populations were long term asbestos workers and women with hydatidiform moles. Our preliminary results indicate abnormal urinary excretion of modified nucleosides and their breakdown products in subjects with lymphadenopathy and Acquired Immune Deficiency Synbdrome (AIDS). To detect carrier state of Acquired Immune Deficiency Syndrome, we propose to study the level of excretion of the nucleoside markers in the urine and serum of several groups of subjects including those with AIDS. The putative high risk group will include patients with chronic lymphadenopathy syndrome and the sexual partners of patients with AIDS. Control group will be age-matched healthy adult male subjects and asymptomatic homosexual men. In addition, we will examine patients with hemophilia. We also hope to determine whether lymphadenopathy is a prodrome of AIDS.